Multifunctional Luminescent Porous Organic Polymer for Selectively Detecting Iron Ions and 1,4-Dioxane via Luminescent Turn-off and Turn-on Sensing

The first case of selective Fe³⁺ ions and 1,4-dioxane luminescent sensor based on a porous organic polymer, POP-HT, was synthesized by reaction of tetra­(p-aminophenyl)­methane and chromophoric 2,5,8-trichloro-s-heptazine. POP-HT displayed prominent fluorescence quenching or enhancement in the presence of Fe³⁺ ion or 1,4-dioxane. Moreover, an excellent linear relationship was established between luminescent intensity and the corresponding Fe³⁺ ion or 1,4-dioxane concentration. The mechanisms of luminescence quenching and enhancement were also studied by both experiment and theoretical calculation. The results of this study suggest that POP-HT can work as an effective luminescent indicator for qualitative and quantitative detection of Fe³⁺ ions and 1,4-dioxane in aqueous solution over other metal ions and organic solvents.